1. Field of the Invention
The present invention relates to a video camera and, more particularly, to a video camera having a negative-positive reversal function.
2. Related Background Art
A video camera having an electronic image pickup element such as a commercial movie camera, an electronic still camera, a TV broadcast camera, or the like is generally equipped with a white balance control circuit for feedback-controlling the amplitudes of R and B components in an image signal of a photographed image. A video camera having a negative-positive reversal function for outputting a negative or positive image as a positive or negative image has also been proposed.
However, as described above, a conventional video camera having both the white balance control function and the negative-positive reversal function performs white-balance control of a photographed image signal, and then performs negative-positive reversal processing. Thus, when a video camera of this type photographs a negative image while performing white-balance control, and outputs a positive image by negative-positive reversal processing of the negative image, the white balance of the positive-output video image is often lost due to the following reason. The film base of a negative film is colored in a predetermined color. As a result, the color of the film base is added to white-balance control as an offset value, and information associated with a color temperature of a light source is reversed and recorded on the negative film. Therefore, when the white-balance control function, which prospects a normal positive image, is directly used, a proper white balance cannot be obtained for a positive output upon a photographing operation of a negative film.
For this reason, in a conventional video camera of this type, when a positive output is obtained upon a photographing operation of a negative film, the automatic white-balance control function is normally disabled.